The invention relates to a refrigeration system having a plurality of cooling surfaces, each of which is connected by way of a series-connected controlled valve to a common refrigerant supply device, and having a control arrangement connected to the valves.
The refrigerant supply device can here be formed by a heat-exchanger in which heat is extracted from brine. The heat is given up to a coolant which is cooled in a customary cooling circuit having one or more compressors, a condenser and a collector, the heat exchanger being provided with an expansion valve. The brine then flows through the cooling surfaces and absorbs heat there in order to cool the environment around the cooling surfaces. In another practical form, the cooling surfaces can also have refrigerant flowing directly through them, the refrigerant being channelled through a circuit containing one or more compressors, a condenser and a collector.
A refrigeration system of the kind mentioned in the introduction is known from EP 0 410 330 A2. The refrigeration system in that case has at least two compressors arranged in parallel in the refrigerant circuit, which compressors can be operated jointly or alternately individually to satisfy the cooling requirement at the various cooling points simultaneously. In this connection it is desirable for the frequency of switching-on of the individual compressors to be reduced in order to prolong their service life. A control arrangement which is connected to thermostatic valves is provided for controlling the compressors. The thermostatic valves relay only the necessary temperature information to the control unit, however, so that this controls the compressors accordingly. The control unit can also switch off individual cooling surfaces when their actual value falls below a predetermined reference value.